The Howard Sheth model, serves as an integrating framework for a very sophisticated comprehensive theory of consumer behavior. It should be noted that the authors actually use the term buyer in their model to refer to industrial purchases as well as ultimate consumers. Thus, it can be seen that their interest was to develop a unified theory useful for understanding a great variety of behaviors.
The model attempts to depict rational brand choice behavior by buyers under conditions of incomplete information and limited abilities. It distinguishes three levels of decision making:
1) Extensive problem solving – early stages of decision making in which the buyer has little information about brands and has not yet developed, well defined and structured criteria by which to choose among products (choice criteria).
2) Limited problem solving – in this more advanced stage choice criteria are well defined but the buyer is still undecided about which set of brands will best serve him. Thus, the consumer still experiences uncertainty about which brand is best.
3) Routinized responses behavior – buyers have well defined choice criteria and also have strong predispositions towards the brand. Little confusion exists in the consumer’s mind and he is ready to purchase a particular brand with little evaluation of alternatives
The model borrows from learning concepts to explain brand choice behavior over time as learning takes place and the buyer moves from exclusive to routinized problem solving behavior. Four major components are involved (1) input variables, (2) output variables (3) hypothetical constructs and (4) exogenous variables.
Input variables are depicted in the left portion of the model as stimuli in the environment. Significance stimuli are actual elements of brands that the buyer confronts while symbolic form, such as in advertisements. Social stimuli are generated by the social environment including family and groups.
Output variables: The five output variables in the right hand portion of the model are buyers’ observable responses to stimulus inputs. They are arranged in order from attention to actual purchase and are defined as follows:
Attention – the magnitude of the buyer’s information intake.
Comprehension – the buyer’s store of information about a brand.
Attitude – the buyer’s evaluation of a particular brand’s potential to satisfy his of her motives.
Intention – the buyers forecast of which brand he or she will buy.
Purchase behavior – the actual purchase act, which reflects the buyer’s predisposition to buy as modified by any inhibitors
A number of intervening variables are proposed, represented by hypothetical constructs in the large rectangular, central black box shown. They are categorized into two major groups: (1) perceptual constructs dealing with information processing and (2) learning constructs dealing with the buyer’s formation of concepts
The three perceptual constructs of the model can be described as follows:
Sensitivity to information – the degree to which the buyer regulates the stimulus information flow.
Perceptual bias — distorting or altering information.
Search for information — active seeking of information about brands or their characteristics
The buyer’s six learning constructs are defined as:
Motive – general or specific goals impelling action.
Brand potential of the evoked set – the buyer’s perception of the ability of brands in his or her evoked set (those that are actively considered) to satisfy his or her goals.
Decision mediators – the buyer’s mental rules for matching and ranking purchase alternatives according to his or her motives.
Predisposition – a preference towards brands in the evoked set expressed as an attitude towards them.
Inhibitors –environmental forces such as price and time pressure which restrain purchase of a preferred brand.
Satisfaction – the degree to which consequences of a purchase measure up to the buyer’s expectations for it.
Source: Consumer Behavior